GOST 1762.6-71
GOST 1762.6−71 Silumin ingots. Methods for determination of copper (with Amendments No. 1, 2)
GOST 1762.6−71
Group B59
STATE STANDARD OF THE USSR
SILUMIN IN PIGS
Methods for determination of copper
Aluminium-silicon alloy ingots.
Methods for determination of copper
AXTU 1709
Valid from 01.01.73
to 01.07.95*
_______________________________
* Expiration removed
Protocol N 4−93 inter-state Council
for standardization, Metrology and certification.
(IUS N 4, 1994). — Note the CODE.
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
THE DEVELOPERS OF THE STANDARD
A. A. Kostyukov, G. A. Romanov, N. M. Gertseva, A. P. Nechitailov, V. A. Lavrov
2. APPROVED AND promulgated by the Decree of the State Committee of standards of Ministerial Council of the USSR from
3. The frequency of inspection — 5 years
4. REPLACE GOST 1762−51 (in terms of sec. VII)
5. REFERENCE NORMATIVE AND TECHNICAL DOCUMENTS
| The designation of the reference document referenced | Item number | |
| GOST 83−79 | 4.2 | |
| GOST 859−78 | 2.2; 3.2; 4.2 | |
| GOST 1762.0−71 | 1.1 | |
| GOST 2062−77 | 3.2 | |
| GOST 3118−77 | 2.2; 3.2; 4.2 | |
| GOST 4038−79 | 4.2 | |
| GOST 4109−79 | 3.2 | |
| GOST 4165−78 | 4.2 | |
| GOST 4166−76 | 2.2 | |
| GOST 4233−77 | 4.2 | |
| GOST 4328−77 | 2.2; 3.2; 4.2 | |
| GOST 4461−77 | 2.2; 3.2; 4.2 | |
| GOST 5457−75 | 4.2 | |
| GOST 9293−74 | 3.2 | |
| GOST 9428−73 | 4.2 | |
| GOST 10157−79 | 3.2 | |
| GOST 10929−76 | 2.2; 4.2 | |
| GOST 11069−74 | 4.2 | |
| GOST 20288−74 | 2.2 | |
| GOST 20298−74 | 2.2 | |
6. Validity extended until
7. The re-release (may 1989) with Amendments No. 1, 2 approved in August 1984, March 1989 (IUS 12−84, 6−89)
This standard sets the photometric method (at a mass fraction of copper from 0.001 to 0.04%), polarographic and atomic absorption methods for the determination of copper (at a mass fraction of copper from 0.005 to 0.1%).
(Changed edition, Rev. N 2).
1. GENERAL REQUIREMENTS
1.1. General requirements for methods of analysis GOST 1762.0−71.
2. PHOTOMETRIC METHOD
2.1. The essence of the method consists in measuring the optical density of the colored complex compounds of copper with diethyldithiophosphate Nickel extractable by carbon tetrachloride.
(Changed edition, Rev. N 2).
2.2. Apparatus, reagents and solutions
Photoelectrocolorimeter FEK-56M, PEC-60, KLF, spectrophotometer SF-16, SF-26 or similar.
Distilled water not containing heavy metals.
Distilled water is purified from traces of heavy metals passing through the layer of strongly acidic cation exchange resin (KU-1, KU-2).
The cation exchanger KU-1, KU-2 according to GOST 20298−74.
All reagents are prepared in purified in such way water.
Cation; prepared as follows: 40−50 g of cation exchange resin, screened from dust, placed in a beaker with a capacity of 300 cm, 80−100 cm poured
hydrochloric acid diluted 1:1 and heated for 30−45 minutes, the Acid decanted and repeatedly washed cation exchange resin with water with stirring, decantation until a neutral reaction on methyl orange. The cation resin is transferred into the column of ground with a faucet on the bottom of which laid a wad of glass wool. A column of cation exchange resin were filled with distilled water, the layer of the cation must always be covered with water. The absorption properties of cation exchanger after its saturation can be restored by treatment with hydrochloric acid and water.
Diethyldithiophosphate Nickel, 0.04 percent aqueous solution.
Sodium hydroxide according to GOST 4328−77, a solution with a mass fraction of 30%. A sample of sodium hydroxide is dissolved in water in Nickel or platinum Cup and, if necessary, filtered through absorbent cotton, collecting the solution in a vessel made of polyethylene.
Sodium sulfate according to GOST 4166−76.
Hydrochloric acid by the GOST 3118−77, diluted 1:1, and the solution with a molar concentration of 0.2 mol/DM.
Nitric acid GOST 4461−77 diluted 1:1.
Hydrogen peroxide according to GOST 10929−76, a solution with a mass fraction of 3%.
Copper GOST 859−78*.
________________
* On the territory of the Russian Federation GOST 859−2001, here and hereafter. — Note the CODE.
Standard solutions of copper
Solution a, prepared as follows: of 0.2000 g of copper is dissolved in 5 cmof nitric acid. After dissolution, add 10 cm
of hydrochloric acid and evaporated to small volume. Evaporation with hydrochloric acid repeated two more times. To the residue add 15 cm
of hydrochloric acid, transfer the solution into a volumetric flask with a capacity of 1 DM
and dilute to the mark with water.
1 cmof solution A contains 0.2 mg of copper.
Solution B is prepared before use by diluting the solution 100 times with water.
1 cmof a solution contains 0.002 mg of copper.
Carbon tetrachloride according to GOST 20288−74.
(Changed edition, Rev. N 1).
2.3. Analysis
2.3.1. A portion of the silumin weighing 0.5 g were placed in a glass with a capacity of 250 cmand poured 20 cm
of the sodium hydroxide solution. After the violent reaction solution is heated until complete dissolution of the alloy is diluted with water and carefully pour 50 cm
of hydrochloric acid diluted 1:1. The solution is heated to enlightenment, add 20−25 drops of hydrogen peroxide and boil for the destruction of its excess. The cooled solution was transferred to volumetric flask with a capacity of 250 cm
, made up to the mark with purified water and mix.
Depending on the copper content of selected aliquot part of the solution 20−100 cmin a separating funnel with a capacity of 250 cm
(the nose cone should be dry), dilute the solution, if necessary, up to 100 cm
with a solution of a molar concentration of 0.2 mol/DM
of hydrochloric acid, add 3 cm
of a solution of diethyldithiophosphate Nickel and poured from the burette (burette tap not oil) 5 cm
of carbon tetrachloride.
The contents of the funnel vigorously shaken for 1 min, then allowed for separation and after phase separation, merge the painted layer of carbon tetrachloride in a dry cylinder with a glass stopper. In a separatory funnel pour another 5 cmof carbon tetrachloride and repeat the extraction. The extract is poured into the same cylinder and stirred.
The organic phase is separated from the water may carefully, avoiding contact with the aqueous phase in the cylinder.
The optical density of test solution is measured on a photoelectrocolorimeter or spectrophotometer, given that a maximum of light absorption of solutions corresponds to a wavelength of 420 nm.
Solution comparison is carbon tetrachloride.
To remove residual moisture during the filling of the cuvette the solutions were passed through a dry ash-free filter or the extracts in the cylinders was added 1 g of anhydrous sodium sulfate.
The copper content found at the calibration schedule, taking into account the amendment in the reference experiment.
2.3.2. Construction of calibration curve
Poured in separating funnel from burette 0; 1,0; 2,0; 3,0; 4,0; 5,0; 7,0; 8,0 cmstandard solution B, which corresponds to 0; 0,002; 0,004; 0,006; 0,008; 0,010; 0,014; 0,016 mg of copper, diluted with a solution of a molar concentration of 0.2 mol/DM
of hydrochloric acid to 100 cm
, pour 3 cm
of a solution of diethyldithiophosphate of Nickel and the extracted of copper diethyldithiophosphate two portions of 5 cm
of carbon tetrachloride.
Further analysis is carried out as specified in clause
Solution comparison is carbon tetrachloride.
According to the obtained values of optical density and known mass of copper in the solutions to build the calibration graph.
2.4. Processing of the results
2.4.1. Mass fraction of copper () in percent is calculated by the formula
where is the mass of copper was found in the calibration graphics mg;
— the total volume of solution, cm
;
— volume aliquote part of the solution, cm
;
— the weight of the portion of silumin,
2.4.2. Allowable absolute differences of the results of the parallel definitions should not exceed the values given in table.1.
Table 1
| Mass fraction of copper, % |
Allowable absolute differences, % | |
| convergence |
reproducibility | |
| From 0.001 to 0.005 incl. |
0,0005 | 0,001 |
| SV. 0,005 «0,010 « | 0,001 | 0,002 |
| «0,010» 0,040 « | 0,002 | 0,003 |
2.3.1
3. POLAROGRAPHIC METHOD
3.1. The essence of the method
The method is based on dissolving the alloy in sodium hydroxide solution, acidification of the alkaline solution bromatological acid to pH 1 and polarography of copper in the range of potentials from minus 0.05 to minus 0.4 V.
(Changed edition, Rev. N 1).
3.2. Apparatus, reagents and solutions
Polarograph AC type PU-1 or similar.
Nitrogen gaseous and liquid technical, GOST 9293−74 or argon gaseous and liquid GOST 10157−79.
Sodium hydroxide according to GOST 4328−77, a solution with a mass fraction of 20%.
Bromatologia acid according to GOST 2062−77, diluted 2:1.
Bromine according to GOST 4109−79.
Nitric acid GOST 4461−77 diluted 1:1.
Ascorbic acid, freshly prepared solution with a mass fraction of 25%.
Copper GOST 859−78.
Standard solutions of copper, 1 g of copper is placed in a beaker with a capacity of 250 cm, is dissolved in 30 cm
of nitric acid, diluted 1:1, wash the side of the Cup with water. The solution was cooled, transferred into a measuring flask with volume capacity of 1000 cm
, is diluted to the mark with water and mix.
1 cmof the solution contains 1 mg of copper.
By appropriate dilution (before applying) prepare a solution with A copper concentration of 0.1 mg per 1 cmof the solution and the solution with a copper concentration of 0.01 mg per 1 cm
of solution.
3.3. Analysis
3.3.1. A portion of the silumin weighing 0.5 g were placed in a glass with a capacity of 100 cm, flow 15 cm
of sodium hydroxide and cover with a watch glass. After the violent reaction solution is heated, boiled for 3−5 min to dissolve the alloy, cooled, diluted with water to a volume of 20 cm
and carefully poured 30 cm
bromatological acid. The solution is heated to enlightenment. After cooling, add 2−3 drops of bromine and again heated to remove excess bromine, bringing the solution volume to 45 cm
. Then added dropwise a solution of ascorbic acid to the bleaching solution. The cooled solution was transferred to volumetric flask with a capacity of 50 cm
, made up to the mark with water and mix.
Cast part of the solution in the electrolyzer with the bottom mercury, pass nitrogen for 5 min and polarography in the range of potentials from minus 0.05 to minus 0.4 V At the desired sensitivity.
The copper content found by the calibration schedule.
(Changed edition, Rev. N 1, 2).
3.3.2. Construction of calibration curve (when the mass fraction of copper from 0.005 to 0.02%)
Three cups with a capacity of 25 cmconsistently poured 0,5; 1,0; 2,0 cm
standard solution B, which corresponds to 0,005; 0,01; 0,02% copper. The solutions were evaporated to dryness on a water bath to the dry residue add aliquot part 10 cm
of one of the studied solutions with less content of copper, mixed, part of the solution placed in the cell and polarographic as specified in claim
From the obtained heights of the peaks subtract the peak height of the investigated diluted solution.
According to the obtained results and the known concentrations of copper to build the calibration graph.
When you replace the capillaries, you need to check the schedule.
3.3.3. Construction of calibration curve (when the mass fraction of copper from 0.01 to 0.1%)
Three cups with a capacity of 25 cmconsistently poured 0,1; 0,5; 1,0 cm
standard solution A, which corresponds to 0,01; 0,05; 0,1% copper. Further analysis is carried out as specified in clause
3.4. Processing of the results
Mass fraction of copper () in percent is determined according to the calibration schedule.
3.4.1. Allowable absolute differences of the results of the parallel definitions should not exceed the values given in table.2.
Table 2
| Mass fraction of copper, % |
Allowable absolute differences, % | |
| convergence |
reproducibility | |
| From 0,005 to 0,010 incl. |
0,001 | 0,002 |
| SV. 0,010 «0,040 « | 0,002 | 0,003 |
| «0,040» 0,100 « | 0,004 | 0,006 |
(Changed edition, Rev. N 2).
4. ATOMIC ABSORPTION METHOD
4.1. The essence of the method
The method is based on measuring atomic absorption of copper in the flame acetylene-air at a wavelength of 324,7 nm.
4.2. Apparatus, reagents and solutions
Spectrometer atomic absorption model of Perkin-Elmer, «Saturn» or similar.
Lamp with a hollow cathode, is intended for the determination of copper.
Acetylene in cylinders for technical GOST 5457−75.
Muffle furnace with thermostat, providing a temperature of 1000 °C.
Hydrochloric acid by the GOST 3118−77, diluted 1:1.
Nitric acid GOST 4461−77 diluted 1:1.
Hydrogen peroxide according to GOST 10929−76, a solution with a mass fraction of 3%.
Aluminium stamps A-999 according to GOST 11069−74*.
________________
* On the territory of the Russian Federation GOST 11069−2001. — Note the CODE.
The solution of aluminum And 20 g/l: 10.0 g of aluminum is placed in a beaker with a capacity of 600 cm
, add 250 cm
of hydrochloric acid diluted 1:1, and dissolved under heating with adding 1 cm
of Nickel chloride. The solution was cooled, transferred to a volumetric flask with a capacity of 500 cm
, is diluted to the mark with water and mix.
Sodium carbonate according to GOST 83−79.
Nickel chloride according to GOST 4038−79, a solution with a mass fraction of 0.2%.
Methyl orange, solution with a mass fraction of 0.1%.
Silicon dioxide according to GOST 9428−73.
A solution of silicon B, 1 g/DM: 2,14 g of finely crushed in an agate or plexiglass mortar and preheated for one hour at a temperature of 1000 °C silicon dioxide is fused in a platinum crucible with 15.0 g of sodium carbonate at a temperature of 900 °C for 15 min to obtain clear water. The smelt is dissolved in water by heating in a platinum, silver or Nickel Cup. The solution was cooled, transferred into a measuring flask with volume capacity of 1000 cm
, is diluted to the mark with water and mix; the solution was stored in a plastic container.
Sodium chloride according to GOST 4233−77.
A solution of sodium oxide, 100 g/l: 190 g dried at 105 °C for 30 min. sodium chloride dissolved in water. The solution was transferred into a measuring flask with volume capacity of 1000 cm
, adjusted to the mark with water and mix.
Sodium hydroxide according to GOST 4328−77, a solution with a mass fraction of 30%.
Copper sulfate 5-water according to GOST 4165−78.
Copper metal according to GOST 859−78.
Standard solutions of copper
Solution D: 3,9258 g of copper sulphate dissolved in water, transfer the solution into a measuring flask with volume capacity of 1000 cm, adjusted to the mark with water and stirred or 1,0000 g copper metal was dissolved in 20 cm
of nitric acid, diluted 1:1. The solution was evaporated to small volume, add 10 cm
of hydrochloric acid and again evaporated to small volume. Evaporation with hydrochloric acid repeated two more times. To the residue add 15 cm
of hydrochloric acid, transfer the solution into a measuring flask with volume capacity of 1000 cm
, is diluted to the mark with water and mix.
1 cmof solution e contains 1 mg of copper.
Solution: pipetted 5 cmof solution D in a volumetric flask with a capacity of 200 cm
, is diluted to the mark with water and mix; prepare before use.
1 cmof solution E contains 0,025 mg IU
di.
4.3. Analysis
4.3.1. Weighed samples of the silumin weighing 0.5 g were placed in a glass with a capacity of 250 cmand poured 20 cm
of the sodium hydroxide solution. After the violent reaction solution is heated until complete dissolution of the alloy, adding 100 cm
of water and carefully to the cooled solution poured 50 cm
of hydrochloric acid diluted 1:1. The solution is heated to enlightenment, add 1 cm
of hydrogen peroxide and boiled for 3−5 min for the destruction of its excess. The solution was cooled, transferred to a volumetric flask with a capacity of 250 cm
, was adjusted to the mark with water and mix.
Simultaneously carried through all stages of the analysis test experience using all the reagents, with the addition of 20 cmof a solution of aluminium A.
Measure the atomic absorption of copper in the sample solution, control solution and experience in solutions, prepared to build a calibration curve at a wavelength of 324,7 nm flame air-acetylene.
Mass fraction of copper is determined according to the calibration schedule, which build on every shot
.
4.3.2. Construction of calibration curve
In seven volumetric flasks with a capacity of 250 cmpoured in 12.5 cm
of solution A with 7 cm
of solution, respectively, to each flask 0; 1,0; 2,0; 3,0; 5,0; 10,0; 20,0 cm
of solution E, which corresponds to 0; 0,005; 0,01; 0,015; 0,025; 0,05; 0,1% the mass fraction of copper silumin. The solutions were adjusted with water to a volume of 100 cm
and slowly portions, stirring thoroughly, pour 25 cm
of a solution, add 3−4 drops of methyl orange indicator and drop hydrochloric acid diluted 1:1, until the color changes of the indicator in red. Then the solutions in the flasks was adjusted to the mark with water, mix and measure the atomic absorption of copper, as specified in clause
According to the obtained values of atomic absorption solutions and the known values of the mass fraction of copper to build the calibration graph.
4.4. Processing of the results
4.4.1. Mass fraction of copper in the cent find the calibration schedule, minus the reference experiment.
4.4.2. Allowable absolute differences of the results of the parallel definitions should not exceed the values given in table.2.
Sec. 4. (Added, Rev. N 2).
